1. Field of the invention
The present invention relates to a screen printing method and a holding table for a plate to be printed used for the method.
2. Description of the Prior Art
A screen printing is so structured as to move a squeegee in a state of bringing a screen into contact with an upper surface of a plate to be printed such as a printed plate board and the like or setting the screen slightly apart therefrom and apply a printing agent such as a creamed solder and the like to the plate to be printed, thereby performing a printing.
Further, during the process, the screen is separated from the plate to be printed after applying the printing agent. In this case, the screen is conventionally wholly lifted up to an immediately upper direction and all the surface is separated simultaneously from the plate to be coated.
However, when all the surface is simultaneously separated as mentioned above, there is a case that the printing agent within a through hole of the screen is left within the through hole without being released out over the printed plate board, especially at the moment the screen is separated at a center portion thereof, depending upon a degree of a viscosity of the printing agent. In this case, an uneven coating of the printing agent on the plate to be printed is generated, so that a problem that a lack of pattern is generated. For this reason, in order to peel off the uneven printing agent conventionally, a peeling operation is performed for ten and some minutes.
Therefore, a lot of producing time is required by the time of completion, and this greatly causes to increase a cost of a product.